Support Jupyter Widgets

[bollwyvl]

Get the JS kernel to support the Jupyter Widget message spec. Unfortunately, the most professionally-maintained JS kernel does't have a story yet so we'll be inventing new stuff.

desired API

How should widgets be available?

• [ ] wydgets whole new API opinion
• [ ] @jupyter-widgets/jupyterlab-manager somehow use the registry directly

let x = widgets.FloatSlider({description: 'x'});
display.display(x);
// a widget appears in the output area
x.value = 1.0
// item moves along axis
x.jsobserve('value', (change) => { document.write(change.new) })
// page streams changed values
widgets.jsdlink([x, 'value'], [x, 'description'], (value) => { `${value} %` }
// some weird labelling stuff happens

approaches

• use the widget registry directly to generate an API of the available widgets?

down the road

• if a live jyve kernel (or proxy) has direct access to the WidgetManager, there's no reason it couldn't have access to all the widgets in all the notebooks, and be able to manage linkages between them.